It is proposed to (1) characterize excitable sodium channels in Electrophorus electricus electroplax membranes, by binding of H3-TTX, scorpion venom toxin, veratrum alkaloids and inorganic cations, (2) to purify solubilized sodium channel components by affinity chromatography on columns of Sepharose-TTX derivatives, (3) to chemically characterize such purified components and to prepare antibodies to them, (4) to use such antibodies to individual channel components to help delineate their function, using Na22 flux either in sealed membrane preparations or in neuroblastoma cells. BIBLIOGRAPHIC REFERENCES: Properties of the Tetrodotoxin binding Component in Plasma Membrane Isolated from Electrophorus electricus. Juta K. Reed and M.A. Raftery. Biochemistry 15, 944 (1976).